what is best to revive an old 1966 hipo 289 engine

[Spooner]

This probably should be listed in another section, but the engine is typically one out of a Mustang. I have been handed down the family I/O ski boat (1966 16' Donzi Ski Sporter). It has been in our family since my dad bought it new in 1966. He swapped out the engine right after he bought it with a new 289 hi po engine and had it built by Dave Zeuschel (balanced, modello modified heads, etc) The dyno shows about 260 horsepower and it probably only has about 200-300 hours by my estimates through all these years.

We recently had the whole boat and engine gone through and it looks great and runs. Replaced the coil and changed out to an electronic distributor, new plugs, wires, oil pump, etc. It is a high compression engine and needs a lead additive, so I have been running premium and add Red-line lead substitute.

I ran the boat this week and it ran great out on the lake, but it is kind of rough at idle. When I tried to bring it down to an idle to shift into gear (docking) it would stall, so we are working on the idle setting in hopes of getting it down. My dad said it used to idle smoothly at low rpm but seems to recall someone tried to winterize it and did something weird and it never idled the same. That probably doesn't help much.

I have run Redline oil and auto RX in my cars with excellent results...Are there any suggestions on the best oil to use on this engine or oil additives to clean things out? Is there anything different I need to consider since this is used for a boat engine or run very few hours? It is a real family jewel and I want to give it the best to keep it running smoothly as we restore the boat.
Thanks for any help...

Bob

 

[Garak]

Originally Posted By: Spooner
I have run Redline oil and auto RX in my cars with excellent results...Are there any suggestions on the best oil to use on this engine or oil additives to clean things out? Is there anything different I need to consider since this is used for a boat engine or run very few hours? It is a real family jewel and I want to give it the best to keep it running smoothly as we restore the boat.
Thanks for any help...


My first instinct would be for an HDEO such as Rotella or Delvac in 15w-40. You'll have plenty of ZDDP and detergent, and it should work nicely in the climate that a boat sees, along with the expected engine loading and revs.

 

[c502cid]

What did you do when you had the engine "gone through"? I only say that because my humble internet opinion would say to freshen that engine up. That much time with so few hours, it's due.
New, gaskets, piston rings, bearings, and especially a valve job (add the hardened unleaded seats!). Carb rebuild wouldn't hurt either. You already did the oil pump.
If you want years of service to go, it really is a small investment!

 

[BigCahuna]

Boats are sorta like motorcycles. They sit for long periods of time and the carbs tend to get varnished up, and the gas gets stale. I would throw some Seafoam in the gas. I tend to overdose my stuff with it, but the key is to run the whole tank out. Just letting it run for 10 minutes wont do much for cleaning the internals.I noticed on my 318 Chrysler, after a hard run when I returned to the dock it would stall when docking. Usually when you didn't need it to. I traced it back to the ignition resister. I had to jump it out to keep the motor running.As far as oil goes, in my old Chrysler and Chevy straight six I ran either straight 30 or 40 wt . Being most boats don't operate in cold weather, and multi vis oils tend to thin out under extreme use, I would use a straight wt oil. Good luck.,,

 

[eljefino]

+1 on the carb problems, I would expect a fairly simple carb but it could still have an idle circuit that's gummed up, they are smaller passages than the main one. The default if you don't idle and troll all the time is to try and richen it up a little esp if you're now cursed with E10 gas on the water. Remember most marine mechanics also work on snowmobiles and ATVs (if you live somewhere with off-seasons) so they have to be jacks of all trades and masters of none.

Boat motor cams are different from car ones, the torque keeps going up and up towards redline on a boat one. That probably means not much vacuum at idle, worsening a bad carb problem by not having much "will to live". However maybe you can adjust the relationship of the throttle lever WRT the neutral position so long as it doesn't slam into gear.

 

[Johnny]

Classic old boats are like classic old cars, overload us with some good pictures.

 

[Spooner]

Thanks for all the input...I should have added that the carb is new and the engine mechanic is a hydroplane boat racer who knows marine engines and personally knew the guy who built this engine (small world). He couldn't believe how nice the engine looked when we had it opened up. We will probably change out the valve seats at some point and do a more thorough "freshening up" when my wallet is a little more flush.
Is there any benefit from adding AutoRX, Seafoam or MMM to the oil?

I have plenty of pictures, but not sure how to post them. I do have a quick video on you tube.

http://www.youtube.com/watch?v=S9qXz4CJS8U

 

[ProStreetCamaro]

When you opened the engine up if everything looked good I wouldn't use any additives in the oil. Just use a good HDEO and call it good.

As for the rough idle are you sure it doesn't have a performance aftermarket cam in it? If the cam is stock then you have some kind of carb issue or timing issue most likely. Right out of the box most new carbs are not tuned correctly.

 

[mechtech2]

Boats usually use different cooling than cars.
They can run at very low temps - too cool in my opinion.

Do you have any gauges in the boat? [oil and water temp, oil pressure, etc.]
You probably have a 'hot' cam n that car. Extra oil protection is needed, but that does not mean just a thicker oil. A HDEO [usually used for diesels] would be great. 5-40 versions are full synthetic.

Your carburetor and fuel system is almost assuredly deposit laden. This will not allow gs to pass through in proper amounts. Also, Gas now has 10% or more alcohol in it, and your carb is jetted for pure gasoline.
A thorough teardown and cleaning is best for the carb at this point.

 

[Steve S]

Make sure the tune is good check for vacume leak. and the carb is clean. Do a compression check .A vacume gauge could really help diagnose the problem. Does the Donzi have offshore styling? After all that the last thing if nothing else proves to be the problem check the valve springs. It is not an oil problem.

 

[Spooner]

It does have a mild cam (iskadarian?) We will check some of those items mentioned, compression is excellent and maybe I can replace valve springs soon. I was thinking of using AutoRX added to the oil just for potential improvement and ease of mind, and maybe run some Redline gas additive through as well.

By offshore styling do you mean the boat itself or is that an engine term? The 16 Donzi Ski Sporter is/was the first offshore type performance boat with the deep vee hull that I know of. In 1966 every other boat was much less "sporty". I put up the youtube link if you want to look at the boat, but I am having a hard time posting any pictures on this thread.

 

[Gene K]

Redline is fine if you want a full synthetic. Boat engines operate at high rpm for long periods of time which can result in higher than expected oil temps given their relatively low water temp. Its really hard to pick an oil grade without knowing what the oil temp is.

If you are going to run non-synthetic an HDEO such as Rotella, Delvac or Delo is fine. They dont have the ZDDP levels they used to though.

 

[mechtech2]

Gene -
Good point about running at 1/2 to open throttle a lot.
Kinda like light aircraft engines in this respect.
But being cooled by lake water does indeed keep things pretty cool.

 

[Spooner]

So...
I have been running the boat with Castrol that was put in by my mechanic (I need to grab a bottle of the extra to make sure which for sure, but I think it is 20/50w GTX).
A few times out and it has been running great, but I want to change out this first oil soon after running a few tankfuls through the motor. I have talked with a few oil companies and they have offered advice and specs, but I am not oil-savvy enough to know the difference between what is marketing and what is actually fact, so I truly value the advice from BITOG members.
Both the folks at Redline and at Torco were extremely helpful on the phone. For my older engine Torco recommended the 20w50 SR-1 Synthetic. One of the things he said was that the addition of zinc was good for the roller cams (sounds like it makes sense).
Can anyone shed some light on the Zinc additive or the Torco Oil quality?

By the way I ordered some of the Torco accelerator (Octane Booster) for getting the octane up with my high compression (10:1)

thanks for all the help so far..

 

[mechtech2]

How much will that octane booster raise the octane? A point per bottle? A point is 0.1, not 1.
10/1 should not need more than 91-92, unless the ignition advance is way too far advanced.
A hot cam will make that 10/1 be much less, effectively. Tthe intake closes later than a stock or mild cam - less compression is the result.

 

[spasm3]

the floats in the carb could have a pinhole if they are brass, or have gotten soaked with fuel if they are plastic. the fuel bowl may be over filling at idle. sometimes its just crud stuck to the floats or a worn needle seat. something to check. rebuilding the carb or replacing it would be a small expense to try first.

 

[Spooner]

Not sure if I was clear but the carb is new (and was tuned/jetted by our mechanic last month, so I feel comfortable with how it is running. Although I may ask him to try and adjust it or the air/fuel mixture again.

The cam is an Iskenderian Cam and has the following specs (from the card)..

(valve timing shows two revolutions 720 degrees of the crankshaft, checked at .007 lifter rise)
Intake timing
Open 32 before tdc
Close 68 after bdc
Cam lift .291
Valve Lift 467

exhaust timing
Open 68 before bdc
close 32 after tdc
valve lift 467

Timing at .050" lifter rise
Intake
Open 4 before tdc
close 40 after bdc

exhaust
open 40 before bdc
close 4 after tdc

On the subject of the octane booster, I have heard both sides of the "points equal ...?" Have you researched the Torco Accelerator product or do you have any first hand experience on it? Several claim that it is the best out there and that it does raise octane by several true points...so I am hearing two sides and still not certain myself until I try it.

I checked on the oil and it is Castrol and the weight is 10w40

one other question I have is on outdrive gear oil...I have my old Eaton series sixteen outdrive (and yes it still runs fine). The manual calls out for "a first grade, heavy duty gear oil, SAE 90 weight, containing Sulphur-Chlorine-Lead additive - or Eaton p/n L-100"

Anyone have some idea of what to use these days? I don't mind paying for whatever is the best.

 

[mechtech2]

A valve seat lubricant may be a good idea, depending on how they were rebuilt and updated. Even MMO in the fuel would help with this. [somewhat]
Do you need octane booster? Andy chance you could get the distributor advance specs?
Ever hear any knocking? Any other evidence of spark knock?
I am just not feeling that you need a special product with your present set up.

 

[Spooner]

I appreciate your feedback. I've been using the redline valve seat additive (lead substitute) since the valve seats are still the old style. From what I heard from Torco, their octane booster (accelerator) has the same type of valve seat lubricants in it. As far as the octane rating required, I was going off of the advice of my dad and the mechanic who worked on it. Both said it was designed to run on leaded premium, which I estimate at about 94 octane back in the day. It ran a little smoother with a higher octane around 94-95 this last weekend. I mixed Trick Racing 101 and some Premium from the pump, but what a pain in the #@@.

I would sure like to get the full scoop on the engine so I know exactly what it needs. This winter I may just pull the engine again and have somebody just open it up and go through the whole thing, replacing or upgrading whatever is needed.

On the distributor advance specs, we replaced the dual points with the pertronix electronic ignition kit (and coil). But sorry I don't know the specs.